Testing and adjusting apparatus for cord-circuits



J. F. TOOMEY.

TESTING AND ADJUSTING APPARATUS FOR com) cmcuns. APPLICATION FILED SEPT. I. 1917.

1,360,331 f Patented Nov. 30, 1920.

inal4 IN VEN TOR.

JFYbome BY Z m.

ATTORNEY J. F. TOOMEY.

TESTING AND ADJUSTING APPARATUS FOR CORD CIRCUITS.

APPLIEATION FILED SEPT. I, I9II.

Patented Nov. 30, 1920.

2 SHEETS-SHEET 2- IN VEN TOR.

A TTORNEY *U N IT E D S T A T PATENT OF FICE.

JOHN F TOOMEY, OF NEW YORK, Y., ASSIGNOR TOALMERICAN TELEPHONE AND TELEGRAPH COMPANY, A CORPORATION OF NEW YORK.

TESTING AND'ADJUS'IING APPARATUS FOR CORD-CIRCUITS.

Specification of Letters Patent.

Patented Nov. 30, 1920.

Application filed. September 1, 1917. Serial No. 189,332.

'1 0 all, 41) 700m it may concern Be it known that I, Join? l lootmr,

residing at New York, in the county of New York and State of New York, have invented certa n Improvements lliTeStlllg and Adusting Apparatus for GO1'Cl--C1ICU1i3S, of

which the following is a specification.

determine whether the supervisory relaysassociated with said cord circuit function properly under conditions which are either approximately the same as or are more se- 'VGI'G than those experienced in actual service; also, to determine whether the ringing key associated vwith the said cord circuit operates properly. p

To provide adjusting equipment whereby the adjusting of the supervisory relays to meet the desired operating conditions may be done in an efficient manner.

To rovide testin e ui' ment in means P3 y a oi? v-Jhich any circuit troubles such as an open circuit or a short circuit in the conductors in the cords may be detected.

(Ether and further objects of the invention will appear from the following description taken in connection with the accompanying drawing, Figures 1 an'd 2 of which, when arranged with Fig. Zto the right of Fig. 1, embody a circuit diagram of the testing and adjusting features of this in vention.

Fig. 1 illustrates a circuit diagram at a standard toll cord c rcuit,term1nating in. the

I usual back and front plugs, P and airespectively, which are adapted for insertion into theusual line jacks (not shownythat are installed in a switch-board. current supervisory relay 1, and an alternating current supervisory relay 12 areassociated with the said cord circuit, whereby the said circuit may be used to establish a supervised connection either between two long distance toll lines, or between a lon distance toll line and a toll switching trun line. It two long distance toll lines are A direct connected by inserting plugs P and P into two line jacks (not shown) in which the said toll lines terminateat a switchboard, the alternating current relay 12 may be energized by the alternating ringing current which may betransmitted over each of said N toll lines. The circuit containing the direct current supervisory relay 1, which is nor mally bridged across the said cord circuit,

is opened by the operation of marginal relay 4: when the cord circuit is used to estab lish a connection between two long distance toll lines, whereby the loss in transmission due to such bridged relay is prevented. If, however, a long distance toll line is connected by saidcord circuit to a toll switching trunk line, over which direct current is transmitted for supervisory purposes, the

alternating current relay 12 may be ener' gized by the alternating ringing current transmitted over the long distance toll line, and the direct current supervisory relay 1 maybe energizedlby the direct currenttrans- .mitted over the toll switching trunk line.

In addition to the usual line jacks, special jacks, J J and 3 am multipled at each switchboard section, in order that the toll "cord circuits located in each switchboard sectionlnay be variously connectedwi'tjh the 'testin circuit shown at the top of Fin, 2. n; a dit'onal jack .1; is a1somu1tipldat each switchboardsection for the purpose of connecting with the testing circuit a suit able indicating instrument 30. Jack J is also multipled at each section of the switchboard for the purpose of connecting to the adjusting circuit shownat the bottom of Fig. "2, any cord circuit, such as that drawn on Fig. 1, the supervisory rerays {of which need adjustment. Jack J shown oh Fig. 2 and hereinafter designated theconti'ol jack, is located at some point sen -sni er to the supervisory relay's'assbf'ciatc d Withthe said cord "circuit, being understood thatin practice the said relays may @be located at some point distant from the switchboard. In order that the adjust-i ing circuit may be controlled from the point at which the said relays are located, a key set K is provided, the plug P ofwhich may be inserted in the control jack J 6 which is located near the supervisory relays. If a becomes locked and restores to its non-operative position any key that has been previously locked. Key 1 controls no circuits, its sole functionbeing to restore to its nonoperative position any key that may be locked, whereas the other keys control contacts whereby the various circuits of the testing and adjusting apparatus are controlled.

Having described generally the circuits and the apparatus shown on the drawing embodied in Figs. 1 and 2, the invention may be made clear by describing the operation of the said circuits and apparatus.

Testing direct current supervisory relay. Assuming that it is desired to make a test in order to determine whether the direct current supervisory relay 1 functions properly, which is one of the principal objects of this invention, plug P is inserted in jack J whereby a "circuit is closed from ground through battery 13,, relay 3, marginal relay 4:, relay 5, sleeve contacts of plug P and jack J lower back contact of relay 6, through resistance R, to ground. Relay 3 and relay 5 are thereby ei'iergized.- Relay 3 closes a circuit fromground, through battery 13,, upper front contact of relay 3, conductor 7 to point 8 where the circuit divides,

part of the current flowing through relay 11, right hand back contact of relay 12 to ground;the remainder of the current flowing through conductor 9, thence through lamp 1?) and winding of relay 1a in parallel, through upper back contact of relay 11,

conductor 37, contact 38 of key 15 to ground until relay 11 is sutliciently energized to open the latter circuit through its u per contact. Due to the fact that relay 11 is of a quick-operating type, and relay 14 is of a slow operating type, sufficient current does not flow through lamp 1 3 and the winding of relay 1%, prior to theopening of the circuit containing them at the contact of relay 11, to light the lamp 13 or to energize and lock up relay 14.

Relay 5 at its upper front contact closes a circuit from ground, battery 13,, resistance B lower back contacts in series of relays 16' and-17, ring contacts of jack J, and plug; P right hand lower back contact of. key

18. conductor 26, lower winding of retardation coil 19, relay 1, back contact of marginal relay 4;, upper winding of retardation coil 19, conductor 28, right hand upper back Contact of key 18, upper front contact of relay 5, tip contacts of plug 1 and jack J,, upper back contacts in series of relays 1'? and 16, upper back contact of relay 6, resistance H through interrupter 20 to ground. Relay 1 will he energized, and if properly adjusted, it will close a circuit from ground through battery B lamp 21, contact of relay 1 to ground, causing the lamp 21 to glow. lVhen said interrupter opens the circuit, relay 1 is deenergized, which results in the opening of the circuit through its contact, and the lamp 21 is 0.;- tinguished. The resistance R, is of such value and the interrupter 20 is so designed as to permit the flow of the minimum current through relay 1, and the maximum rate of flashing of the lamp 21 that will occur under actual operating conditions. If lamp 21 flashes properly, relay 1 may be considered satisfactorily adjusted for the conditions described.

In order to test the operation of the direct current supervisory relay 1 under the condition of maximum current and minimum rate of flashing of the lamp 21, plug P is left inserted in jack d and the key 13 is operated so as to apply ringing current over the right hand springs to the testing circuit, whereby a circuit is closed from ground, ringing generator 22, right hand lower front contact of key 18, ring contact of plug P, and jack J lower back contacts in series of relays 17 and 16, through condenser 23, relay 24, upper back contacts in series of relays 16 and 17, tip contacts of jack J and plug P upper front contact of relay 5, right hand upper front contact of key 18 to ground, which will energize relay 2%, thereby closing a circuit from ground. contact of relay 24, upper winding of relay 6, battery 13, to ground. After applying ringing current as described above. key 18 is restored to its normal position. Relay (3 is energized, closing through its lower front contact a locking circuit from ground, hattery 13,, lower winding of relay 3. relay 4-. relay 5, sleeve contacts of plug l, and jack J,, lower front contact of relay (3. lower winding of relay 6 to ground, which locks relay 6: Through the upp r front contact of relay 6.. a circuit is closed from ground. interrupter 25, resistance R upper front llll jack J lowerback contacts in series of relays 17 and 16, resistance R battery B to ground. If the relay 1 is properly adjusted, it will close a circuit from ground,-hattery B lamp 21, contact of relay 1 to ground, causing the lamp to glow. When the interrupter 25 opens said circuit, relay 1 should he de-energized, thereby opening the circuit through its contact, so that lamp 21 is extinguished. Resistance R, is of such value and interrupter 25 is so designed as to perunit the maximum current to flow through relay 1, for the maximum length of time that will occur under actual operating conditions, so that if there is a tendency for the relay to remain operated, the trouble will be readily noted by the action of lamp 21. Furthermore, the difference in the flashing rate indicates to the testing operator that the testing circuit is operating properly. If the direct current supervisory relay 1 operates satisfactorily under these two tests,

it may be considered properly adjusted. Test 0 f alternating current supervisory relay.

To determine whether the alternating current supervisory relay 12 is properly adusted the following test 1s made. Plug P,

's left inserted in jack J, and plug P, is in- 1 left hand lower back contact of key 18, ring contacts of plug l. and jack J resistances and R to the lower front contact of relay 16, thus forming a circuit through ring side of both cords. Also, by the energization of relay 16, a circuit is closed from upper front contact of relay 16, upper back contact of relay 17, tip contacts of jack J, and plug P front contact of relay 5, right hand upper back contact of key 18., conductor 28,

upper contacts of key 27, left hand upper back contacts of key 18, tip contacts of plug P and jack J resistances R, and R to the upper front contact of relay 16. thus forming a circuit through the tip side of both cords. The alternating current supervisory relay 12 is bridged across the ringside and the tip side-0f the above-mentloned circuits 1 at a point between splitting key 27 and ringing key 18.

Resistances R, andR in series in the tip side of the line and and R, in series in the ring side of the line, together with resistanceli bridged across the line, represent an artificial line, one end. of which terminates in jack J, and "the other end in jack J Relay 8 was energized when plug P,

around. Relay 16 was inserted in jack J and the results of its operation have already been described under Testing direct current supervisory relay".

In order totest the alternating current supervisory relay 12, key 148 is thrown to the right so as to apply ringing-current to the cord terminating in Plug P,. A circuit is closed from ground, right hand upper front-contact of key 18, front contact of relay 5, tipcontacts of plug P and jack J upper back contact of relay 17, upper front contact of relay 16, resistances R and 11,, tip contacts of jack J and plug P, left hand upper back contact of key 18, through relay 12, left hand lower back contact of key 18, the ring contacts of plug P and jack J resistances R -and R lower front contact of relay 16, lower back contact of relay 17, ring contacts of jack J, and plugP,, to right hand lower front contact of key 18 through ringing generator 22 to ground. Relay 12 is energized, and, if properly adjusted, opens the circuit through relay 11 which closes a circuit from ground, battery 13,, front contact of relay 3, conductors 7 and 9, through lamp 13 and winding of relay 14 in parallel, hack contact of relay 11, conductor 37, contact 88 of key 15 to ground, energizing relay 14 and causing lamp 13 to glow. Relay 14: operates and locks up through a circuit from .ground, battery 13,, front contact of relay 8, conductors 7 and 9, through lamp 13 and winding of relay 14: in parallel, front contact of relay 14:, conductor 37, contact 38 of key 15 to ground. Lamp 13 will continue to glow until contact 38 is opened, which, in actual service, occurs when an operator throws key 15 to the right so as to bridge her telepluuie set across the line, in response to the signal given. by the lighting of lamp N If key 18 is thrown to the left so as to a) a] rin in current to 3111 P, a circuit closed from ground, through left hand upper front contact of key 18, tip contacts of plug P, and jack d resistances R, and R upper front contact of relay 16 and upper back contact of relay 17, tip contacts of jack J, and plug 1 front contact of upper back contact of through upper conav 12, lower contacts of relay 5, right hen" key/'18, con

key 27, conductor 28, right hand lower back contact of key 18, ring contacts of plug P and jack 5,, lower back contact of relay 17, lower front contact of relay 16, resistances R and hl ring contacts of jack J, and plug P left hand lower front contact of key 18, through ringing generator 22 to ground. Relay 12 if properly adjusted is energized, and the lamp is caused to glow as before described. By means of these two tests not only is the operation of relay 12 observed, but also the condition of the contacts. of, keys 27 and 18,*since a defective ,right'hand lower back contact of key conductor 26, lower contacts of key 27, left key contact will prevent the closing of the clrcuit through relay 12, thereby rendering the said relay inoperatlve.

' rd tests.

It sometimes happens that the stranded conductors in a cord become opened or crossed. If the conductors of the cord circuit are entirely opened or crossed, the trouble will be detected in the test for the adjustment of the relays previously described. If the trouble consists in broken strands in the conductors, which increases the resistance of the cord and impairs the transmission, it ma be detected by the following-test: Plug l is left inserted in jack .1, and plug P isinserted in jack J of which the tip and the ring contacts are short circuit-ed. When plug P, is inserted in jack J, a circuit is closed from ground through battery 13,, upper winding of relay 3, sleeve contacts of plug P and jack J winding of relay 17 to ground, whereby relay 1? is energized, closing circuit from ground through battery 13,, lower winding of re tardation coil 29, lower front contact of relay 17, ring contacts of jack J and plu 7) hand lowerback contact of key 18, ring contacts of plug P and jack J through shortcircuiting strap to tip contacts of jack J and plug P left hand upper back contact of key 18, upper contacts of key 2?, conductor 28, right hand upper back contact of key 18, front contact of relay 5, tip contacts of plug P, and jack J upper front contact of relay 17, through upper winding of retardation coil 29 to ground. Plug P to which is connected receiver 30 or other suitable indicating instrument, is inserted in jack J the tip and ring contacts of which are bridged across the tip and ring sides respectively of the circuit just described. W hen the cord circuit and the receiver and source of current are associated as described, it will be seen that the conductors of the cord are connected in parallel with the receiver andthat both the conductors and the receiver-are bridged across the ends of the windings of the retardation coil and hat- 7 tery. The voltage across the receiver and the conductors of the cord depends upon the drop in potential across the retardation coil and this voltage can be varied only by changing the current through the said coil. Since the resistance of the receiver is constant, such change in the current through the retardation coil. can be effected only by changing the resistance of the cord circuit. Hence if all or. part of the strands of the cord are broken and if the cord remains in a fixed position, no variation in current will occur and 3 consequently noindication will be given by the receiver". If the cord be forcibly shaken,

the resistance of the conductors will vary greatly, thereby causing a corresponding rapid change in the voltage across the receiver which produces a sputtering noise in the receiver. In this manner breaks in the strands of the conductors may be readily detected.

Adjustment of direct current supcr visorg relay.

If the tests previously made show that the supervisory relays need adjusting in order to obtain satisfactory operation, the following procedure is pursued: Plug l is inse ted in ack J and plug 1 is inserted in jack J Plug P, is associated with a. portable key set K comprising keys 1, 2, 3, i and. 5, key 1 being non-locking, keys 2, 3, 1 and 5 being of the well-known locking type.

In order to adjust the direct current supervisory relay 1. with the plugs inserted as stated above, key 2 may be depressed whereby current will flow through the sleeve contacts of plug P, and jack J sleeve contacts of jack J 6 and plug 1 resistance R contact of key 2, tip contacts of plug P, and jack J relays -31 and 32 to ground. Relay 32 is marginal and does not operate because resistance 1%,, is of such value as to limit the rurrent flowing through relay 62 to an amount that is less than the normal operating current for this relay. Relay 31 operates, closing a circuit from ground through interrupter 33,1csistance It lower back contact of relay 3%, upper back contact of relay 32, upper front contact of relay 31, tip contacts of jack J and plug 1 upper front contact of relay 5, right hand upper back contact of key 18, upper winding of retarda tion coil 19. back contact of relay 4, relay 1, lower winding of retardation coil 19, right hand lower back contact of key 18, ring contacts of plug P, and jack J lower front contact of relay 31. through middle back contact of relay 52 and battery B to ground. Resistance R is usually of such value as to limit the flow of current to the minimum found in practice, and the interrupter 33 is so designed as to create the maximum number of interruptions of the current that may be experienced under actual service conditions. When relay 1 has been adjusted so that it will operate satisfactorily under the above-mentioned conditions, key 3 is depressed, restoring key 2 and closing a circuit from battery, sleeve contacts of jack J and plug P resistance R to contact 39 where the circuit divides, part of current flowing through ring contacts of plug P, and jack J winding of relay 34 to ground, andthe remainder of the current flowing throu 'h the tip contacts of plug P, and jack 3,, and relays 31 and 32 to ground, thereby operating relay 31, but not relay 32, which is marginal. Relay 34; is operated,

.occur under actual service conditions.

manner thereby disconnecting interrupter 33 from the adjusting circuit just described, and connecting interrupter 35 through resistance R to the said adjusting circuit. Resistance R is usually of such value, and interrupter 35 is so designed asto permit the flow of the maximum current with the minimum number of interruptions that may be ex perienced under actual service conditions. After relay 1. has been ad usted so that it will operate satisfactorily under this condidin-stances of alternating Genre 12 75. same-re osory relay.

With the plugs left inserted as in the previous test, restoring key 1 is operated so as to restore any of the locking keys which may have been locked down during the previous test, and key 4: is thendepressed, clos ing a circuit from grounded battery, sleeve contacts of jack J and plu P contactof key 4-, tip contacts of plug 4 and jack J rela 31 and relay 32 to ground, thereby operating both relays 31 and 32. Relay 32 closes a circuit from ground through ringing generator 36, lower front contact of relay 32, resistances R and R upper front contact of relay 32, upper front contact oi? relay 31, tip contacts of jack J 5 and plug P upper front contact of relay 5, right hand upper back contact of key 18, conductor 28, upper back contacts of key 27, through relay 12, lower back contacts oi key 27, conductor 26, right hand lower back contact of key 18, ring contacts of plug P, and jack J lower front contact of relay 3?, middle front contact of relay 32, through resistances R and R to ground. Resistances R R R and 13,, which are in series with the circuit just described, together with re sistances R and R which in series are bridged across said circuit constitute two artificial lines which may be of such values as to permit the flow through relay 12 of the maximum and minimum current that migllit s may be seen, resistance R is normally shortcircuited through the upper back contact of relay 34, so that normally resistance R alone is effectively bridged across the two sides of the line.

With key 4 depressed, relay 34 being nonenergized, the minimum ringing current will flow through relay 12 over the circuit previously described, and the relay may be properly adjusted so as to operate under this condition, which represents the condition met with over the longest line with which the relay will be associated. Then, if key 5 is depressed, key 4 is restored to its normal position, and a circuit is closed from grounded battery, through sleeve contacts of jack J and plug 1 to contact 4L0 where the circuit divides, part of current flowing throu h. the tip contacts of plug P and jack e. and relays 31 and 32 to ground, op erating relays 31 and 32, and the remainder of the current flowing through the ring contarts of plug P and. jack J and relay 3%; to ground. operating relay 34: and opening the short circuit around resistance R which effectively connects resistance R in series with R across the line. clupervisory relay 12 may then be adjusted, if necessary, to operate under this condition which corresponds with the condition that exists when the cord circuit is connected with the shortest trunk line that is met with in practice. If the relay meets the requirements oi. this test, key 4: may be depressed, restoring key 5 to its normal position, and the relay may again be tested to determine whether it will respond to the minimum ringii'ig current. It the relay responds properly under both conditions, its adjustment may be considered satisfactory.

It should. be imderstood that the resist ances used. in the interru iiter circuit, and in the alternating current circuit may be or such value or values that the current that flows through the circuit will be either the as or somewhat less than the mint inuun, or somewhat greater than the iii-aximum current which iiows under actual serv ice conditions.

It will now be clear that by this invention a simple, convenient and ctlicient ar rangement of circuits has been devised whereby any toll cord may be plugged into a convenient testing jack and the iun'tioning of the various apparatus associated with the said cord circuit may be determined either directly or by manipulating the keys associated with the cord circuit. If any apparatus is found defective on such test, the cord with whi h the defective apparatus is associated may be plugged into a jack leading to an adjusting circuit, whereby the defective apparatus may be controlled by a key set from a point adjacent to such apparatus, and thereby the defective apparatus may be adjusted in a convenient and eflicient manner.

While the invention has been disclosed as if embodied in certain specific organizations and arrangements, it is to be understood. that this embodiment may be widely varied without departing from the spirit of the invention as defined in the appended claims.

. ith,

by ringing current applied through the ringing keys oi said cord circuit.

2. i testing system. comprising a telephone cord circuit having direct current and alternating current relays associa ed therecircuit having sources oi? current associated therewith, means to associate said cord circuit with said testing circuit, and -meansassociat with said resting circuit whereby tie flow of current through each of said relays may be controlled.

A. testing system comprising a telphone cord clrcuit located at a swi and having direct current and altern current relays associated with said ca 011- cuit, a testing circuit, means to connect said cord circuit to said testing circuit, and means associated with said circuit whereby the flow of current may be controlled by an operator from said switchboard.

4. A testing system comprising a telephone cord circuit, a testing circuit, means whereby both ends of the said cord circuit may be connected to the said testing circuit, and means associated with said testing circuit whereby a combination of resistances simulating an actual telephone line is bridged across the two ends of said cord circuit.

5. A testing system comprising atelephone cord circuit, a testing circuit having a source of current in series with a retardation coil bridged acrossone end thereof, an indicating instrument bridged across said testing circuit in parallel with said source and coil, means to connect one end of said cord circuit to said testing circuit and means to short circuit the other end of said cord circuit whereby defects in said cord circuit 'may be determined when the cords of said testing circuit, and means associated with said testing circuit whereby the flow of current through said relays may be controlled from a point adjacent to said relays.

7. A testing system comprising a telephone cord circuit at a switchboard having relays associated therewith, a testing circuit having a source of current and a plurality of interruptcrs associalcd therewith. mains to connect said cord. circuit with said testing circuit, and means located at said switchboard to connect any one oi? said interruptcrs in series with said source o'l' current and said relays whereby said relays may lie intermittently energized.

8. A testing system 'o1i1 ,ui:%in-- a lclcphone cord circuit having relay s ociatcd therewith, a testing circuit having a source of current and a plurality o interriu icrs assoc ted therewith, means for i-ouiux'rtin r said cord circuit with said testing circuit whereby said interrupted current may flow through said relays. and means whereby lhc K 1 nine or" said interrupted current. llo wiu y through said relays, may be limited.

9. A testing system comprising a telephone cord circuit having direct cu rrcnt and alternating cu "rent relays associa ed ther with, a testing circuit having sources of interru 'ited direct current and a terualf. current, a circuit controlling set, incurs to connect said cord circuit with said testing circuit, means to connect said circuit controlling set with said testing circuit, and means rcsponsive to the operation of said circuit controlling set whereby either a direct current or an alternating current relay may bc caused to respond.

10. A testing system comprising a plurality oi telephone cordv circuits located at a switchboard and having direct and alternating current relays associated tllcl'NVil'll, a testing circuit havin a plurality of switching means associated therewith and located at said switchboard to connect any of said cord circuits with said testing circuit, sources of direct current and 4 crnating current associated with said testing circuit and located at a point remote from said switchboard, and so tching means associated with said testing circuitand adjacent to said relays to connect a circuit controlling set with aid testing circuit whereby any of said relays associated with any of said cord circuits may be controlled i'rom a point adjacent to said relays.

In testimony whereof, I have signed my name to this specification this twenty-eighth day of August, 1917.

JOHN F. TOOMEY. 

